TECHNICAL FIELD
[0001] The present disclosure relates generally to cleaning and assessment systems and methods,
and more particularly to, cleaning and assessment systems and methods for a tip of
an airfoil of a bladed rotor.
BACKGROUND
[0002] Gas turbine engines (such as those used in electrical power generation or used in
modern aircraft) typically include a compressor, a combustor section, and a turbine.
The compressor and the turbine typically include a series of alternating rotors and
stators. A rotor generally comprises a rotor disk and a plurality of airfoils. The
rotor may be an integrally bladed rotor ("IBR") or a mechanically bladed rotor.
[0003] The rotor disk and airfoils in the IBR are one piece (i.e., monolithic, or nearly
monolithic) with the airfoils spaced around the circumference of the rotor disk. Conventional
IBRs may be formed using a variety of technical methods including integral casting,
machining from a solid billet, or by welding or bonding the airfoils to the rotor
disk.
[0004] Tips of airfoils for IBRs are often coated with a coating having an abrasive material,
such a as cubic boron nitride ("cBN") coating or the like. The abrasive material is
configured to interface with an abradable material disposed radially adjacent to the
airfoil tip and coupled to a case, or any other surrounding support structure in the
gas turbine engine. Initially, the abrasive material of the coating cuts into the
abradable material, forming a trench, a recess, or the like. The coating is configured
protect the tips of airfoils for the IBRs from burning up during operation.
[0005] At various maintenance intervals, or overhaul, for the gas turbine engine, each tip
of an airfoil having the coating disposed thereon is inspected. Inspections are typically
performed visually (i.e., in person or with pictures), which can be time consuming
due to the number of airfoils in a compressor section of an aircraft, and provide
inconsistent success criteria for determining whether a tip of an airfoil is acceptable
for entry back into service.
SUMMARY
[0006] A method is disclosed herein. The method comprises: flowing a potted component in
a liquid state over a tip of an airfoil, the tip of the airfoil having a coating disposed
thereon, the coating comprising a metal plating and a plurality of protrusions, each
protrusion in the plurality of protrusions extending from the metal plating; allowing
the potted component to harden to form a hardened potted component; and removing the
hardened potted component from the tip of the airfoil.
[0007] In various embodiments, loose particles are coupled to the potted component in response
to allowing the potted component to harden. The method can further comprise creating
a mold of the tip of the airfoil with a second potted component. The method can further
comprise analyzing a molded surface of the mold to determine whether the plurality
of protrusions of the coating contain sufficient coverage of the tip of the airfoil.
The method can further comprise replacing the coating in response to determining the
coating does not maintain sufficient coverage.
[0008] In various embodiments, the hardened potted component defines a mold of the tip of
the airfoil, the mold including a mold surface having a plurality of recesses. The
method can further comprise: scanning the mold; and comparing a recess density for
each local area of the mold surface to a recess density threshold corresponding to
a protrusion density threshold of the plurality of protrusions. The method can further
comprise determining, based on the comparison, whether the coating maintains sufficient
coverage for the airfoil to be placed back in service. The method can further comprise
replacing the coating in response to determining the coating does not maintain sufficient
coverage.
[0009] A method is disclosed herein. The method comprises: receiving, via a processor, scanner
data for a mold corresponding to a tip of an airfoil of a bladed rotor, the tip including
a coating disposed thereon, the coating comprising a metal plating and a plurality
of protrusions; comparing, via the processor, a coating parameter of the coating to
a coating parameter threshold for the tip of each airfoil of the bladed rotor based
on the mold; and determining, via the processor, whether the coating parameter of
the airfoil of the bladed rotor does not meet the coating parameter threshold.
[0010] In various embodiments, the method further comprises receiving, via the processor,
scanner data for a plurality of molds, each mold in the plurality of molds corresponding
to a respective tip of a respective airfoil in a plurality of airfoils of the bladed
rotor. The method can further comprise receiving, via the processor, an identifier
for each mold in the plurality of molds, the identifier corresponding to the respective
airfoil in the plurality of airfoils of the bladed rotor. The method can further comprise:
determining whether the coating parameter for any airfoil in the plurality of airfoils
of the bladed rotor does not meet the coating parameter threshold; and replacing the
coating of the tip of the airfoil in response to determining the coating parameter
of the coating does not meet the coating parameter threshold. In various embodiments,
the coating parameter is protrusion density.
[0011] In various embodiments, the method further comprises generating, via the processor,
an indication the coating on the tip of the airfoil should be replaced in response
to determining a recess density in a mold surface of the mold in a local area of the
mold surface is below a recess density threshold corresponding to a protrusion density
threshold of the coating.
[0012] A coating assessment system is disclosed herein. The system comprises: a scanner;
a display; and a tangible, non-transitory computer-readable storage medium having
instructions stored thereon that, in response to execution by a processor, cause the
processor to perform operations comprising: receiving, via the processor, scanner
data for a mold corresponding to a tip of an airfoil of a bladed rotor, the tip including
a coating disposed thereon, the coating comprising a metal plating and a plurality
of protrusions; analyzing, via the processor, the mold to determine whether the coating
is supplying sufficient coverage to the tip of the airfoil; and generating, via the
processor and through the display, an indication that the coating should be replaced
in response to determining a coating parameter does not meet a coating parameter threshold.
[0013] In various embodiments, the coating parameter includes a protrusion density.
[0014] In various embodiments, the analyzing the mold includes comparing a recess density
in a local area of a mold surface of the mold to a recess density threshold, the recess
density corresponding to the coating parameter, the recess density threshold corresponding
to the coating parameter threshold. In various embodiments, the recess density corresponds
to a number of recesses in the mold surface per unit area.
[0015] In various embodiments, the scanner is one of an optical scanner, a mechanical scanner,
a laser scanner, a non-structured optical scanner, or a non-visual scanner. The forgoing
features and elements may be combined in various combinations without exclusivity,
unless expressly indicated herein otherwise. These features and elements as well as
the operation of the disclosed embodiments will become more apparent in light of the
following description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The subject matter of the present disclosure is particularly pointed out and distinctly
claimed in the concluding portion of the specification. A more complete understanding
of the present disclosure, however, may best be obtained by referring to the following
detailed description and claims in connection with the following drawings. While the
drawings illustrate various embodiments employing the principles described herein,
the drawings do not limit the scope of the claims.
FIG. 1A illustrates a cross-sectional view of a gas-turbine engine, in accordance
with various embodiments;
FIG. 1B illustrates a cross-sectional view of a high pressure compressor, in accordance
with various embodiments;
FIG. 2A illustrates a perspective view of a bladed rotor, in accordance with various
embodiments;
FIG. 2B illustrates a side view of a portion of an airfoil of a bladed rotor, in accordance
with various embodiments;
FIG. 3 illustrates a method of inspecting and assessing a tip of an airfoil for a
bladed rotor, in accordance with various embodiments;
FIG. 4A illustrates a tip of an airfoil of a bladed rotor during a cleaning process,
in accordance with various embodiments;
FIG. 4B illustrates a tip of an airfoil of a bladed rotor during a cleaning process,
in accordance with various embodiments;
FIG. 4C illustrates a tip of an airfoil of a bladed rotor during a cleaning process,
in accordance with various embodiments;
FIG. 5A illustrates a tip of an airfoil of a bladed rotor during a cleaning process;
FIG. 5B illustrates a tip of an airfoil of a bladed rotor during a molding process,
in accordance with various embodiments;
FIG. 5C illustrates a tip of an airfoil of a bladed rotor during a molding process,
in accordance with various embodiments;
FIG. 6 illustrates an airfoil tip assessment system in use, in accordance with various
embodiments;
FIG. 7 illustrates a digital representation from a scanner of the airfoil tip assessment
system, in accordance with various embodiments; and
FIG. 8 illustrates an assessment process performed by the airfoil tip assessment system,
in accordance with various embodiments.
DETAILED DESCRIPTION
[0017] The following detailed description of various embodiments herein refers to the accompanying
drawings, which show various embodiments by way of illustration. While these various
embodiments are described in sufficient detail to enable those skilled in the art
to practice the disclosure, it should be understood that other embodiments may be
realized and that changes may be made without departing from the scope of the disclosure.
Thus, the detailed description herein is presented for purposes of illustration only
and not of limitation. Furthermore, any reference to singular includes plural embodiments,
and any reference to more than one component or step may include a singular embodiment
or step. Also, any reference to attached, fixed, connected, or the like may include
permanent, removable, temporary, partial, full or any other possible attachment option.
Additionally, any reference to without contact (or similar phrases) may also include
reduced contact or minimal contact. It should also be understood that unless specifically
stated otherwise, references to "a," "an" or "the" may include one or more than one
and that reference to an item in the singular may also include the item in the plural.
Further, all ranges may include upper and lower values and all ranges and ratio limits
disclosed herein may be combined.
[0018] As used herein, "aft" refers to the direction associated with the tail (e.g., the
back end) of an aircraft, or generally, to the direction of exhaust of the gas turbine.
As used herein, "forward" refers to the direction associated with the nose (e.g.,
the front end) of an aircraft, or generally, to the direction of flight or motion.
[0019] With reference to FIG. 1A, a gas turbine engine 20 is shown according to various
embodiments. Gas turbine engine 20 may be a two-spool turbofan that generally incorporates
a fan section 22, a compressor section 24, a combustor section 26, and a turbine section
28. In operation, fan section 22 can drive air along a path of bypass airflow B while
compressor section 24 can drive air along a core flow path C for compression and communication
into combustor section 26 then expansion through turbine section 28. Although depicted
as a turbofan gas turbine engine 20 herein, it should be understood that the concepts
described herein are not limited to use with turbofans as the teachings may be applied
to other types of turbine engines including three-spool architectures, single spool
architecture or the like.
[0020] Gas turbine engine 20 may generally comprise a low speed spool 30 and a high speed
spool 32 mounted for rotation about an engine central longitudinal axis A-A' relative
to an engine static structure 36 or engine case via several bearing systems 38, 38-1,
etc. Engine central longitudinal axis A-A' is oriented in the Z direction on the provided
X-Y-Z axes. It should be understood that various bearing systems 38 at various locations
may alternatively or additionally be provided, including for example, bearing system
38, bearing system 38-1, etc.
[0021] Low speed spool 30 may generally comprise an inner shaft 40 that interconnects a
fan 42, a low pressure compressor 44 and a low pressure turbine 46. Inner shaft 40
may be connected to fan 42 through a geared architecture 48 that can drive fan 42
at a lower speed than low speed spool 30. Geared architecture 48 may comprise a gear
assembly 60 enclosed within a gear housing 62. Gear assembly 60 couples inner shaft
40 to a rotating fan structure. High speed spool 32 may comprise an outer shaft 50
that interconnects a high pressure compressor 52 and high pressure turbine 54. A combustor
56 may be located between high pressure compressor 52 and high pressure turbine 54.
A mid-turbine frame 57 of engine static structure 36 may be located generally between
high pressure turbine 54 and low pressure turbine 46. Mid-turbine frame 57 may support
one or more bearing systems 38 in turbine section 28. Inner shaft 40 and outer shaft
50 may be concentric and rotate via bearing systems 38 about the engine central longitudinal
axis A-A', which is collinear with their longitudinal axes. As used herein, a "high
pressure" compressor or turbine experiences a higher pressure than a corresponding
"low pressure" compressor or turbine.
[0022] The core airflow may be compressed by low pressure compressor 44 then high pressure
compressor 52, mixed and burned with fuel in combustor 56, then expanded over high
pressure turbine 54 and low pressure turbine 46. Turbines 46, 54 rotationally drive
the respective low speed spool 30 and high speed spool 32 in response to the expansion.
[0023] In various embodiments, and with reference to FIG. 1B, high pressure compressor 52
of the compressor section 24 of gas turbine engine 20 is provided. The high pressure
compressor 52 includes a plurality of blade stages 101 (i.e., rotor stages) and a
plurality of vane stages 105 (i.e., stator stages). The blade stages 101 may each
include a bladed rotor 100. In various embodiments, the bladed rotor 100 is an integrally
bladed rotor, such that the airfoils 103 (e.g., blades) and rotor disks 102 are formed
from a single integral component (i.e., a monolithic component formed of a single
piece). However, the present disclosure is not limited in this regard. For example,
the bladed rotor 100 can comprise a mechanically bladed rotor (i.e., each airfoil
103 mechanically coupled to the rotor disk 102). The airfoils 103 extend radially
outward from the rotor disk 102. The gas turbine engine 20 may further include an
exit guide vane stage 106 that defines the aft end of the high pressure compressor
52. Although illustrated with respect to high pressure compressor 52, the present
disclosure is not limited in this regard. For example, the low pressure compressor
44 may include a plurality of blade stages 101 and vane stages 105, each blade stage
in the plurality of blade stages 101 including the bladed rotor 100 and still be within
the scope of this disclosure. In various embodiments, the plurality of blade stages
101 forms a stack of bladed rotors 110, which define, at least partially, a rotor
module 111 of the high pressure compressor 52 of the gas turbine engine 20.
[0024] An outer engine case 120 is disposed radially outward from a tip of each airfoil
103. The outer engine case 120 comprises an abradable material 122 disposed radially
adjacent to the tip of each airfoil 103. In this regard, the tip of each airfoil 103
comprises a coating, as described further herein, that includes an abrasive material.
The abrasive material is configured to interface with the abradable material 122 of
the outer engine case during operation of the gas turbine engine 20. Initially, the
abrasive material of the coating cuts into the abradable material, forming a trench,
a recess, or the like. The coating is configured protect the tips of airfoils 103
for the bladed rotors 100 from burning up during operation of the gas turbine engine
20.
[0025] Referring now to FIG. 2, a perspective view of a bladed rotor 200 is illustrated
in accordance with various embodiments. The bladed rotor 200 can be in accordance
with any of the bladed rotors 100 from FIG. 1A. The present disclosure is not limited
in this regard. The bladed rotor 200 comprises a hub 202, a rotor disk 204 defining
a platform 205, and a plurality of airfoils 206. Each airfoil in the plurality of
airfoils 206 extends radially outward from the platform 205. For example, an airfoil
210 in the plurality of airfoils 206 extends radially outward from a root 212 of the
airfoil 210 to a tip 214 of the airfoil. The root 212 can be integral with the platform
205 or coupled to the platform 205 as described previously herein. The present disclosure
is not limited in this regard.
[0026] Referring now to FIG. 2B, a detail view of portion of the airfoil 210 from FIG. 2A
is illustrated, in accordance with various embodiments. Each airfoil in the plurality
of airfoils 206 from FIG. 2A is in accordance with the airfoil 210. The airfoil 210
comprises a coating 220 disposed on the tip 214 of the airfoil 210. In various embodiments,
the coating 220 comprises a metal plating 221 (e.g., a nickel plating or the like),
and an abrasive material (e.g., alumina, cubic boron nitride, silicon carbide, tungsten
carbide, silicon nitride, or titanium diboride) extending outward from the metal plating
221. For example, the coating 220 includes a plurality of protrusions 222 (i.e., grits).
Each protrusion in the plurality of protrusions 222 extends radially outward from
the tip 214 of the airfoil 210 (e.g., towards the abradable material 122 from FIG.
1B when installed). In various embodiments, each protrusion in the plurality of protrusions
222 of the coating 220 comprises cubic boron nitride.
[0027] Referring now to FIG. 3, a method 300 for assessing a tip of an airfoil for a bladed
rotor (e.g., bladed rotor 200) is illustrated, in accordance with various embodiments.
The method 300 comprises cleaning a tip 214 of airfoil 210 of a bladed rotor 200 (step
302). In various embodiments, the method 300 includes cleaning each tip 214 for each
airfoil 210 of the bladed rotor 200. In this regard, all airfoils 210 of a bladed
rotor may be cleaned prior to proceeding in method 300. In various embodiments, cleaning
the tip 214 of the airfoil 210 of bladed rotor 200 may include disposing a potting
component. A "potting component," as described herein may be a thermoplastic elastomer,
silicone, silicone rubber, natural rubber, epoxy, or the like. With brief reference
to FIGs. 4A-C, a potting component 402 may be flowed over, in a liquid, or semi-liquid,
state, the tip 214 of an airfoil 210 to cover the entirety of the tip 214 (FIG. 4A).
Once the potting component 402 hardens, the potting component 402 may be removed off
of the tip 214 of the airfoil 210 as shown in FIGs. 4B and 4C. In this regard, loose
particles 224 from the tip 214 of the airfoil 210 may be removed from the airfoil
210. In various embodiments, the loose particles include abradable material 122 as
described previously herein. In various embodiments, the loose particles 224 comprise
protrusions from the plurality of protrusions 222, which were loosened during operation.
[0028] Referring back to FIG. 3, the method 300 further comprises scanning the tip 214 of
the airfoil 210 (step 304). The method 300 comprises cleaning a tip 214 of airfoil
210 of a bladed rotor 200 (step 302). Although method 300 is described with respect
to a single tip of a single airfoil, the present disclosure is not limited in this
regard. For example, steps of method 300 may be performed for the tip of each airfoil
of a bladed rotor 200 prior to moving on to a next step, in accordance with various
embodiments. For example, the method 300 can include cleaning the tip 214 for each
airfoil 210 of the bladed rotor 200. In this regard, all airfoils 210 of a bladed
rotor may be cleaned prior to proceeding in method 300, then scanned in step 304,
then analyzed in step 306, and so on. Thus, an inspection and analysis time for determining
whether the tip 214 of each airfoil 210 in the plurality of airfoils 206 of the bladed
rotor 200 may be greatly reduced relative to typical inspection and analysis systems
and methods.
[0029] In various embodiments, cleaning the tip 214 of the airfoil 210 of bladed rotor 200
may include disposing a potting component. A "potting component," as described herein
may be a thermoplastic elastomer, silicone, silicone rubber, natural rubber, epoxy,
or the like. With brief reference to FIGs. 4A-C, a potting component 402 may be flowed
over, in a liquid state, or pushed onto the surface in a semi-liquid state, the tip
214 of an airfoil 210 to cover the entirety of the tip 214 (FIG. 4A). Once the potting
component 402 hardens, the potting component 402 may be removed off of the tip 214
of the airfoil 210 as shown in FIGs. 4B and 4C. In this regard, loose particles 224
from the tip 214 of the airfoil 210 may be removed from the airfoil 210. In various
embodiments, the loose particles 224 include abradable material 122 as described previously
herein. In various embodiments, the loose particles 224 comprise protrusions from
the plurality of protrusions 222, which were loosened during operation.
[0030] In various embodiments, the method 300 further comprises creating a mold of the tip
of the airfoil of the bladed rotor (step 304). The mold may be created in a similar
manner to the cleaning step 302. For example, with reference now to FIGs. 5A-C, a
second potting component 404 can be flowed over, in a liquid state, the tip 214 of
the airfoil 210 to cover the entirety of the tip 214 (FIG. 5A). Once the second potting
component 404 hardens, the potting component 404 can be removed off of the tip 214
of the airfoil 210 as shown in FIGs. 5B and 5C. As the tip was previously cleaned
in step 302, there will be no loose particles 224 in the second potting component
404. In this regard, after removal of the second potting component 404, a mold 405
defining a mold surface 406 with a complimentary shape to the tip 214 of the airfoil
210 is created, in accordance with various embodiments.
[0031] Referring back to FIG. 3, the method 300 further comprises scanning the mold 405
of the tip 214 of the airfoil 210 of the bladed rotor 200 (step 306). With reference
now to FIG. 6, an airfoil tip assessment system 600 for performing step 306 of method
300 is illustrated, in accordance with various embodiments. The airfoil tip assessment
system 600 includes a scanner 650 and a computer-based system 601 including a controller
610, a graphical user interface (GUI) 616, and a display 618. In various embodiments,
by scanning the mold 405 from step 304, as opposed to the tip 214 of the airfoil 210
directly can be significantly easier to handle due to being significantly smaller
in size relative to the bladed rotor. Similarly, the tip 214 of the airfoil 210 could
be inspected and assessed in an installed state without taking the bladed rotor 200
off the gas turbine engine 20, in accordance with various embodiments. Thus, an airfoil
tip inspection time may be greatly reduced for a bladed rotor 200, in accordance with
various embodiments.
[0032] In various embodiments, the computer-based system 601 comprises a controller 610.
In various embodiments the GUI 616, display 618, and the scanner 650 are in electronic
communication (e.g., wireless or wired) with the scanner 650. In various embodiments,
controller 610 may be integrated into computer system. In various embodiments, controller
610 may be configured as a central network element or hub to access various systems
and components of the airfoil tip assessment system 400. Controller 610 may comprise
a network, computer-based system, and/or software components configured to provide
an access point to various systems and components of the inspection system. In various
embodiments, controller 610 may comprise a processor 612. In various embodiments,
controller 610 may be implemented in a single processor. In various embodiments, controller
610 may be implemented as and may include one or more processors and/or one or more
tangible, non-transitory memories (e.g., memory 614) and be capable of implementing
logic (e.g., memory 614). Each processor can be a general purpose processor, a digital
signal processor (DSP), an application specific integrated circuit (ASIC), a field
programable gate array (FPGA) or other programable logic device, discrete gate or
transistor logic, discrete hardware components, or any combination thereof. Controller
610 may comprise a processor 612 configured to implement various logical operations
in response to execution of instructions, for example, instructions stored on a non-transitory,
tangible, computer-readable medium (e.g., memory 614) configured to communicate with
controller 610.
[0033] System program instructions and/or controller instructions may be loaded onto a non-transitory,
tangible computer-readable medium having instructions stored thereon that, in response
to execution by a controller, cause the controller to perform various operations.
The term "non-transitory" is to be understood to remove only propagating transitory
signals per se from the claim scope and does not relinquish rights to all standard
computer-readable media that are not only propagating transitory signals per se. Stated
another way, the meaning of the term "non-transitory computer-readable medium" and
"non-transitory computer-readable storage medium" should be construed to exclude only
those types of transitory computer-readable media which were found in In Re Nuijten
to fall outside the scope of patentable subject matter under 35 U.S.C. ยง 101.
[0034] In various embodiments, the scanner 650 comprises an optical scanner (e.g., structured
light scanners, such as white light scanners, structured blue light scanners, or the
like), a mechanical scanner, a laser scanner, a non-structured optical scanner, a
non-visual scanner (e.g., computed tomography), or the like. In various embodiments,
the scanner 650 provides scanner data illustrating elemental particle distribution.
Thus, a user can distinguish between nickel alloys, titanium alloys, cubic boron nitride
of a coating, etc. Thus, based on scanner data from the scanner 650, a coating 220
of a tip 214 of an airfoil 210 can be assessed in a more accurate and precise manner
as described further herein.
[0035] In various embodiments, in response to scanning the mold 405, a digital representation
of the mold 405 (e.g., a point cloud, a surface model, or the like) can be received
by the controller 610 and converted to a two-dimensional or three-dimensional model
(e.g., a Computer Aided Design (CAD) model or the like). The mold surface 406 includes
a plurality of recesses 422 corresponding to the plurality of protrusions 222 of the
coating 220. In this regard, the two-dimensional or three-dimensional model can be
analyzed, as described further herein to determine whether a total coverage of the
plurality of protrusions 222 are sufficient for the airfoil 210 to be placed back
in service, in accordance with various embodiments.
[0036] Referring back to FIG. 3, the method 300 further comprises analyzing the model (e.g.,
the three-dimensional or two-dimensional model) of the mold 405 for the tip 214 of
the airfoil (step 308). In various embodiments, the computer-based system 401 of the
airfoil tip assessment system 600 is configured to analyze the model of the mold 405.
For example, referring now to FIG. 7, a model 700 based on scanner data (e.g., a point
cloud, a surface model, or the like) from the scanner 650, is illustrated, in accordance
with various embodiments. The model 700 includes a two-dimension or three dimensional
digital rendering 705 of the mold 405 defining digital recesses 704 corresponding
to the recesses 422 from FIG. 6. Based on the model 700, each and every local area
of the mold 405 of the tip 214 the airfoil 210 can be analyzed to determine if the
local area has a recess density above a recess density threshold.
[0037] For example, a local area 702 can be analyzed by comparing a number of digital recesses
704 to a threshold number of recesses (i.e., corresponding to an acceptable number
of protrusions for the tip 214 of the airfoil 210). In various embodiments, the local
area 702 comprises seven recess (i.e., corresponding to seven protrusions for the
tip 214 of the airfoil 210), where the local area 702 typically has nine recesses
(i.e., corresponding to seven protrusions for the tip 214 of the airfoil 210) when
originally manufactured. Although the typical newly manufactured coating for an airfoil
tip includes nine protrusions in the local area 702, a protrusion threshold (i.e.,
to achieve acceptable abradable characteristics of coating 220), six protrusions may
be acceptable. Each recess in the plurality of recesses 422 corresponds to a protrusion
in the plurality of protrusions 222 of the coating 220. Thus, the term "protrusions"
are used when referring to the tip 214 of the airfoil 210 and the term "recesses"
is used when referring to the mold 405 of the tip 214 of the airfoil, in accordance
with various embodiments. Similarly, a "recess density threshold" for the mold 405
corresponds to a "protrusion density threshold" for the tip 214 of the airfoil 210
to achieve acceptable abradable characteristics of coating 220. "Protrusion density"
as referred to herein is a number of protrusions per unit area in the plurality of
protrusions 222 of the coating 220. Similarly, "recess density" as referred to herein
is a number of recess per unit area in the plurality of recesses 422 of the mold 405.
Although described herein as utilizing protrusion density / recess density, the present
disclosure is not limited in this regard. For example, other coating parameters, such
as surface roughness can be utilized and are still within the scope of this disclosure.
[0038] In various embodiments, a recess threshold for the local area 702 may be six protrusions
or greater. In various embodiments, by analyzing a three-dimensional, or two dimensional
digital representation, and comparing to acceptable criteria for a coating 220 being
inspected at various maintenance intervals or overhaul, a significantly more consistent,
precise, and reliable, and/or efficient assessment process can be developed.
[0039] Referring back to FIG. 3, the method 300 further comprises determining, based on
the analysis of step 308, whether the coating maintains sufficient coverage (step
310). In this regard, an entire mold surface 406 of a mold 405 corresponding to a
tip 214 of an airfoil 210 can be analyzed based on the model 700 (e.g., a digital
representation) in FIG. 7, and if any local area (e.g., local area 702) is determined
to have a recess density less than a recess density threshold, then the controller
410 of the airfoil tip assessment system 400 displays the coating 220 at the tip 214
of the airfoil 210 as having to be replaced.
[0040] The method 300 further comprises replacing the coating 220 with a new coating in
response to determining the coating 220 does not maintain sufficient coverage (step
310). Replacing the coating 220 may be a time intensive process, in accordance with
various embodiments. In this regard, by accurately and consistently assessing a coating
220 of an airfoil, unnecessary replacement of coating 220 may be eliminated, greatly
decreasing an overhaul or maintenance interval for a bladed rotor 200, in accordance
with various embodiments.
[0041] Referring now to FIG. 8, an assessment process 800 performed by the airfoil tip assessment
system 600 from FIG. 6, is illustrated, in accordance with various embodiments. The
assessment process 800 comprises receiving, via the processor 612, scanner data (e.g.,
a point cloud, a surface model, or the like) from the scanner 650 for a mold 405 having
a mold surface 406 corresponding to a tip 214 of an airfoil 210 in a plurality of
airfoils 206 of a bladed rotor 200 (step 802).
[0042] In various embodiments, the receiving step 802 further comprises receiving an identifier
for the mold 405. In this regard, after creating a mold, in accordance with step 304
of method 300 from FIG. 3, an identifier may be coupled to the mold 405 (e.g., a radio
frequency identification (RFID) tag, a barcode, or the like). The identifier can correspond
to an airfoil in the bladed rotor 200. In this regard, a mold 405 for the tip 214
of each airfoil 210 in the plurality of airfoils 206 of the bladed rotor 200 can be
scanned in succession, and all airfoils for the bladed rotor 200 can be assessed simultaneously
via the process 800. In this regard, inspection and assessment efficiency for the
tip 214 of each airfoil 210 of the bladed rotor 200 can be greatly improved relative
to typical visual inspection and measurements.
[0043] The process 800 further comprises comparing, via the processor 612, a coating parameter
(e.g., surface roughness, recess/protrusion density, etc.) to a coating parameter
threshold for the tip 214 of each airfoil 210 in the plurality of airfoils 206 of
the bladed rotor 200 (step 804). In various embodiments, the comparison is made by
determining a recess density in the mold surface 406 and comparing the recess density
to a recess density threshold corresponding to a protrusion density threshold for
an acceptable tip 214 of the airfoil 210. In this regard, a recess density determined
in step 704 of process 800 corresponds directly to a protrusion density of the tip
214 of the airfoil 210 from which the mold was molded.
[0044] The process 800 further comprises determining, via the processor 612, whether the
coating parameter of the airfoil of the bladed rotor does not meet the coating parameter
threshold (step 806). In response to not meeting the coating parameter threshold,
the processor 612 generates an indication that the coating 220 on the tip 214 of the
airfoil 210 corresponding to the mold 405 should be replaced (step 708). In this regard,
the mold 405 can be analyzed to determine whether the coating 220 corresponding to
the mold maintains sufficient coverage for the airfoil 210 to re-enter service.
[0045] In various embodiments, the process 800 is more efficient and less time consuming
relative to visual inspections typically employed for assessing coverage of a coating
on a tip of an airfoil. In various embodiments, scanning the molds 405 for the tip
214 of each airfoil 210 can be performed very efficiently due to their significantly
smaller size relative to a bladed rotor 200 and ease of handling relative to the bladed
rotor 200. In various embodiments, the cleaning process described herein (e.g., step
302 of method 300 and FIGs. 4A-4C) provide an efficient method of removing loose particles
224 from a tip 214 of an airfoil 210 prior to an assessment of the tip 214, in accordance
with various embodiments.
[0046] Benefits, other advantages, and solutions to problems have been described herein
with regard to specific embodiments. Furthermore, the connecting lines shown in the
various figures contained herein are intended to represent exemplary functional relationships
and/or physical couplings between the various elements. It should be noted that many
alternative or additional functional relationships or physical connections may be
present in a practical system. However, the benefits, advantages, solutions to problems,
and any elements that may cause any benefit, advantage, or solution to occur or become
more pronounced are not to be construed as critical, required, or essential features
or elements of the disclosure. The scope of the disclosure is accordingly to be limited
by nothing other than the appended claims, in which reference to an element in the
singular is not intended to mean "one and only one" unless explicitly so stated, but
rather "one or more." Moreover, where a phrase similar to "at least one of A, B, or
C" is used in the claims, it is intended that the phrase be interpreted to mean that
A alone may be present in an embodiment, B alone may be present in an embodiment,
C alone may be present in an embodiment, or that any combination of the elements A,
Band C may be present in a single embodiment; for example, A and B, A and C, B and
C, or A and B and C. Different cross-hatching is used throughout the figures to denote
different parts but not necessarily to denote the same or different materials.
[0047] Systems, methods, and apparatus are provided herein. In the detailed description
herein, references to "one embodiment," "an embodiment," "various embodiments," etc.,
indicate that the embodiment described may include a particular feature, structure,
or characteristic, but every embodiment may not necessarily include the particular
feature, structure, or characteristic. Moreover, such phrases are not necessarily
referring to the same embodiment. Further, when a particular feature, structure, or
characteristic is described in connection with an embodiment, it is submitted that
it is within the knowledge of one skilled in the art to affect such feature, structure,
or characteristic in connection with other embodiments whether or not explicitly described.
After reading the description, it will be apparent to one skilled in the relevant
art(s) how to implement the disclosure in alternative embodiments.
[0048] Furthermore, no element, component, or method step in the present disclosure is intended
to be dedicated to the public regardless of whether the element, component, or method
step is explicitly recited in the claims. No claim element herein is to be construed
under the provisions of 35 U.S.C. 112(f) unless the element is expressly recited using
the phrase "means for." As used herein, the terms "comprises," "comprising," or any
other variation thereof, are intended to cover a non-exclusive inclusion, such that
a process, method, article, or apparatus that comprises a list of elements does not
include only those elements but may include other elements not expressly listed or
inherent to such process, method, article, or apparatus.
[0049] Finally, it should be understood that any of the above described concepts can be
used alone or in combination with any or all of the other above described concepts.
Although various embodiments have been disclosed and described, one of ordinary skill
in this art would recognize that certain modifications would come within the scope
of this disclosure. Accordingly, the description is not intended to be exhaustive
or to limit the principles described or illustrated herein to any precise form. Many
modifications and variations are possible in light of the above teaching.
1. A method, comprising:
flowing a potted component in a liquid state over a tip of an airfoil, the tip of
the airfoil having a coating disposed thereon, the coating comprising a metal plating
and a plurality of protrusions, each protrusion in the plurality of protrusions extending
from the metal plating;
allowing the potted component to harden to form a hardened potted component; and
removing the hardened potted component from the tip of the airfoil.
2. The method of claim 1, wherein loose particles are coupled to the potted component
in response to allowing the potted component to harden.
3. The method of claim 2, further comprising creating a mold of the tip of the airfoil
with a second potted component.
4. The method of claim 3, further comprising analyzing a mold surface of the mold to
determine whether the plurality of protrusions of the coating contain sufficient coverage
of the tip of the airfoil.
5. The method of claim 4, further comprising replacing the coating in response to determining
the coating does not maintain sufficient coverage.
6. The method of claim 1 or 2, wherein the hardened potted component defines a mold of
the tip of the airfoil, the mold including a mold surface having a plurality of recesses.
7. The method of claim 6, further comprising:
scanning the mold; and
comparing a recess density for each local area of the mold surface to a recess density
threshold corresponding to a protrusion density threshold of the plurality of protrusions.
8. The method of claim 7, further comprising determining, based on the comparison, whether
the coating maintains sufficient coverage for the airfoil to be placed back in service,
optionally further comprising replacing the coating in response to determining the
coating does not maintain sufficient coverage.
9. A method, comprising:
receiving, via a processor, scanner data for a mold corresponding to a tip of an airfoil
of a bladed rotor, the tip including a coating disposed thereon, the coating comprising
a metal plating and a plurality of protrusions;
comparing, via the processor, a coating parameter of the coating to a coating parameter
threshold for the tip of each airfoil of the bladed rotor based on the mold; and
determining, via the processor, whether the coating parameter of the airfoil of the
bladed rotor does not meet the coating parameter threshold.
10. The method of claim 9, further comprising receiving, via the processor, scanner data
for a plurality of molds, each mold in the plurality of molds corresponding to a respective
tip of a respective airfoil in a plurality of airfoils of the bladed rotor, and/or
further comprising generating, via the processor, an indication the coating on the
tip of the airfoil should be replaced in response to determining a recess density
in a mold surface of the mold in a local area of the mold surface is below a recess
density threshold corresponding to a protrusion density threshold of the coating.
11. The method of claim 9 or 10 , further comprising receiving, via the processor, an
identifier for each mold in the plurality of molds, the identifier corresponding to
the respective airfoil in the plurality of airfoils of the bladed rotor, and/or
the method further comprising:
determining whether the coating parameter for any airfoil in the plurality of airfoils
of the bladed rotor does not meet the coating parameter threshold; and
replacing the coating of the tip of the airfoil in response to determining the coating
parameter of the coating does not meet the coating parameter threshold.
12. The method of any of claims 9, 10 or 11, wherein the coating parameter is protrusion
density.
13. A coating assessment system, comprising:
a scanner;
a display; and
a tangible, non-transitory computer-readable storage medium having instructions stored
thereon that, in response to execution by a processor, cause the processor to perform
operations comprising:
receiving, via the processor, scanner data for a mold corresponding to a tip of an
airfoil of a bladed rotor, the tip including a coating disposed thereon, the coating
comprising a metal plating and a plurality of protrusions;
analyzing, via the processor, the mold to determine whether the coating is supplying
sufficient coverage to the tip of the airfoil; and
generating, via the processor and through the display, an indication that the coating
should be replaced in response to determining a coating parameter does not meet a
coating parameter threshold.
14. The coating assessment system of claim 13, wherein the coating parameter includes
a protrusion density, and/or
wherein the analyzing the mold includes comparing a recess density in a local area
of a mold surface of the mold to a recess density threshold, the recess density corresponding
to the coating parameter, the recess density threshold corresponding to the coating
parameter threshold, and/or
wherein the scanner is one of an optical scanner, a mechanical scanner, a laser scanner,
a non-structured optical scanner, or a non-visual scanner.
15. The coating assessment system of claim 14, wherein the recess density corresponds
to a number of recesses in the mold surface per unit area.